To be used with a Common Emitter test jig as described Here
The value of RCm [ RC modified by ro ] must be less than the total collector load RC∥RL ~ The calculated value of rbb must be positive and the negative result negative for the answer to be plausible
~ NaN [Not a Number] may indicate the measured gain or some other inputs are not correct or a non numeric input was entered
See also ~ rbb calculated from data–sheet values but check the data–sheet figures are the units required for the calculator and the bandwidth used for the measurement
" Check out the work itself ~ A mix of elegance and function "